Improving End-to-End Speech Processing by Efficient Text Data Utilization with Latent Synthesis

Training a high performance end-to-end speech (E2E) processing model requires an enormous amount of labeled speech data, especially in the era of data-centric artificial intelligence. However, labeled speech data are usually scarcer and more expensive for collection, compared to textual data. We propose Latent Synthesis (LaSyn), an efficient textual data utilization framework for E2E speech processing models. We train a latent synthesizer to convert textual data into an intermediate latent representation of a pre-trained speech model. These pseudo acoustic representations of textual data augment acoustic data for model training. We evaluate LaSyn on low-resource automatic speech recognition (ASR) and spoken language understanding (SLU) tasks. For ASR, LaSyn improves an E2E baseline trained on LibriSpeech train-clean-100, with relative word error rate reductions over 22.3% on different test sets. For SLU, LaSyn improves our E2E baseline by absolute 4.1% for intent classification accuracy and 3.8% for slot filling SLU-F1 on SLURP, and absolute 4.49% and 2.25% for exact match (EM) and EM-Tree accuracies on STOP respectively. With fewer parameters, the results of LaSyn are competitive to published state-of-the-art works. The results demonstrate the quality of the augmented training data.Comment: 15 pages, 8 figures, 8 tables, Accepted to EMNLP 2023 Finding

Visual/Inertial/GNSS Integrated Navigation System under GNSS Spoofing Attack

Visual/Inertial/GNSS (VIG) integrated navigation and positioning systems are widely used in unmanned vehicles and other systems. This VIG system is vulnerable to of GNSS spoofing attacks. Relevant research on the harm that spoofing causes to the system and performance analyses of VIG systems under GNSS spoofing are not sufficient. In this paper, an open-source VIG algorithm, VINS-Fusion, based on nonlinear optimization, is used to analyze the performance of the VIG system under a GNSS spoofing attack. The influence of the visual inertial odometer (VIO) scale estimation error and the transformation matrix deviation in the transition period of spoofing detection is analyzed. Deviation correction methods based on the GNSS-assisted scale compensation coefficient estimation method and optimal pose transformation matrix selection are proposed for VIG-integrated system in spoofing areas. For an area that the integrated system can revisit many times, a global pose map-matching method is proposed. An outfield experiment with a GNSS spoofing attack is carried out in this paper. The experiment result shows that, even if the GNSS measurements are seriously affected by the spoofing, the integrated system still can run independently, following the preset waypoint. The scale compensation coefficient estimation method, the optimal pose transformation matrix selection method and the global pose map-matching method can depress the estimation error under the circumstances of a spoofing attack

Benificial effect of stachydrine on the traumatic brain injury induced neurodegeneration by attenuating the expressions of Akt/mTOR/PI3K and TLR4/NFκ-B pathway

Present investigation aims to explore the protective effect of stachydrine against traumatic brain injury (TBI) and also investigate the molecular mechanism of its action. TBI was induced by the fall a hammer (450 g) from the height of 1.5 m. and later stachydrine was administered for 2 weeks starting 2 hr after the induction of TBI. Effect of stachydrine was determined by estimating modified neurological severity score (mNSS), percentage of water content in the brain and cognitive dysfunction in TBI rats. Moreover western blot assay, histopathology and enzyme linked immunosorbent assay (ELISA) tests were used to determine the effect of stachydrine on TBI injured rats. Result of the report suggests that stachydrine reduces the mNSS and percentage of water content in the brain and also attenuates the cognitive dysfunction in TBI injured rats. However data of western blot assay reports that stachydrine reduces the expression of PI3K/m-TOR/Akt pathway in the brain tissues of TBI rats. Concentration of interleukin (IL-1β), tumor necrosis factor-α (TNF-α) and interferon gamma (INF-γ) was reduces in stachydrine treated group than TBI group. Moreover expression of Nuclear factor-κB/Toll-like receptor 4 (NF-κB/TLR-4) protein was also decreased in stachydrine treated group than TBI group. Histopathology study on brain tissue reveals that the percentage of apoptotic cells was also reduced in stachydrine treated group than TBI group. Data of this investigation concludes that stachydrine protects the neuronal injury by attenuating the phosphatidylinositide 3-kinases/mammalian target of rapamycin/Protein kinase B (PI3K/m-TOR/Akt) and NF-κB/TLR-4 pathway in TBI injured rats